What if global warming can't be halted by reducing emissions?

Geoengineering projects are proposed as stopgap measures that could tilt the atmospheric balance back toward cooler temperatures.

Some call for spraying sulfur dioxide in the stratosphere to create a reflective haze, blocking solar radiation. Others propose spreading iron in the oceans to encourage the growth of marine organisms, absorbing carbon dioxide.

But is this wise? While humanity is a problem-solving species, our natural geoengineering—through fuels we burn, crops we plant, and cities we build—is part of the problem.

According to climate scientist James Lovelock, organisms that alter the environment to their own benefit are likelier to survive. A self-regulating flux has thus emerged between the plants, plankton, microbes, and fungi that keep our atmosphere livable—life makes life possible and has done so for milli...
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